salt.modules.sensehat

Module for controlling the LED matrix or reading environment data on the SenseHat of a Raspberry Pi.

maintainer:Benedikt Werner <1benediktwerner@gmail.com>, Joachim Werner <joe@suse.com>
maturity:new
depends:sense_hat Python module

You can specify the rotation of the Pi in a pillar. This is useful if it is used upside down or sideways to correct the orientation of the image being shown.

Example:

sensehat:
    rotation: 90
salt.modules.sensehat.clear(color=None)

Sets the LED matrix to a single color or turns all LEDs off.

CLI Example:

salt 'raspberry' sensehat.clear
salt 'raspberry' sensehat.clear '[255, 0, 0]'
salt.modules.sensehat.get_humidity()

Get the percentage of relative humidity from the humidity sensor.

salt.modules.sensehat.get_pixel(x, y)

Returns the color of a single pixel on the LED matrix.

x
The x coodrinate of th pixel. Ranges from 0 on the left to 7 on the right.
y
The y coodrinate of th pixel. Ranges from 0 at the top to 7 at the bottom.

Note

Please read the note for get_pixels

salt.modules.sensehat.get_pixels()

Returns a list of 64 smaller lists of [R, G, B] pixels representing the the currently displayed image on the LED matrix.

Note

When using set_pixels the pixel values can sometimes change when you read them again using get_pixels. This is because we specify each pixel element as 8 bit numbers (0 to 255) but when they're passed into the Linux frame buffer for the LED matrix the numbers are bit shifted down to fit into RGB 565. 5 bits for red, 6 bits for green and 5 bits for blue. The loss of binary precision when performing this conversion (3 bits lost for red, 2 for green and 3 for blue) accounts for the discrepancies you see.

The get_pixels method provides an accurate representation of how the pixels end up in frame buffer memory after you have called set_pixels.

salt.modules.sensehat.get_pressure()

Gets the current pressure in Millibars from the pressure sensor.

salt.modules.sensehat.get_temperature()

Gets the temperature in degrees Celsius from the humidity sensor. Equivalent to calling get_temperature_from_humidity.

If you get strange results try using 'get_temperature_from_pressure'.

salt.modules.sensehat.get_temperature_from_humidity()

Gets the temperature in degrees Celsius from the humidity sensor.

salt.modules.sensehat.get_temperature_from_pressure()

Gets the temperature in degrees Celsius from the pressure sensor.

salt.modules.sensehat.low_light(low_light=True)

Sets the LED matrix to low light mode. Useful in a dark environment.

CLI Example:

salt 'raspberry' sensehat.low_light
salt 'raspberry' sensehat.low_light False
salt.modules.sensehat.set_pixel(x, y, color)

Sets the a single pixel on the LED matrix to a specified color.

x
The x coodrinate of th pixel. Ranges from 0 on the left to 7 on the right.
y
The y coodrinate of th pixel. Ranges from 0 at the top to 7 at the bottom.
color
The new color of the pixel as a list of [R, G, B] values.

CLI Example:

salt 'raspberry' sensehat.set_pixel 0 0 '[255, 0, 0]'
salt.modules.sensehat.set_pixels(pixels)

Sets the entire LED matrix based on a list of 64 pixel values

pixels
A list of 64 color values [R, G, B].
salt.modules.sensehat.show_image(image)

Displays a 8 x 8 image on the LED matrix.

image
The path to the image to display. The image must be 8 x 8 pixels in size.

CLI Example:

salt 'raspberry' sensehat.show_image /tmp/my_image.png
salt.modules.sensehat.show_letter(letter, text_color=None, back_color=None)

Displays a single letter on the LED matrix.

letter
The letter to display
text_color
The color in which the letter is shown. Defaults to '[255, 255, 255]' (white).
back_color
The background color of the display. Defaults to '[0, 0, 0]' (black).

CLI Example:

salt 'raspberry' sensehat.show_letter O
salt 'raspberry' sensehat.show_letter X '[255, 0, 0]'
salt 'raspberry' sensehat.show_letter B '[0, 0, 255]' '[255, 255, 0]'
salt.modules.sensehat.show_message(message, msg_type=None, text_color=None, back_color=None, scroll_speed=None)

Displays a message on the LED matrix.

message
The message to display
msg_type

The type of the message. Changes the appearence of the message.

Available types are:

error:      red text
warning:    orange text
success:    green text
info:       blue text
scroll_speed
The speed at which the message moves over the LED matrix. This value represents the time paused for between shifting the text to the left by one column of pixels. Defaults to '0.1'.
text_color
The color in which the message is shown. Defaults to '[255, 255, 255]' (white).
back_color
The background color of the display. Defaults to '[0, 0, 0]' (black).

CLI Example:

salt 'raspberry' sensehat.show_message 'Status ok'
salt 'raspberry' sensehat.show_message 'Something went wrong' error
salt 'raspberry' sensehat.show_message 'Red' text_color='[255, 0, 0]'
salt 'raspberry' sensehat.show_message 'Hello world' None '[0, 0, 255]' '[255, 255, 0]' 0.2